Porous Polishing Pad and Preparing Method of the Same

ABSTRACT

The present disclosure relates to a porous polishing pad including pores formed by a reaction between a prepolymer and a saccharide material, and a method of preparing the porous polishing pad.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2015-0155076 filed on Nov. 5, 2015, the disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a porous polishing pad including pores formed by a reaction between a prepolymer and a saccharide material, and a method of preparing the porous polishing pad.

BACKGROUND

Semiconductor devices are formed from a flat, thin wafer of a semiconductor material such as silicon. The wafer needs to be polished to have a sufficiently flat surface with no or minimal defects. Various chemical, electrochemical, and chemical mechanical polishing techniques are employed to polish the wafers. For many years, optical lenses and semiconductor wafers have been polished by a chemical-mechanical means. In particular, with the rapid advancement in the field of semiconductor technology, very large scale integrated (VLSI) and ultra large scale integrated (ULSI) circuits have been developed. Accordingly, more elements can be integrated in a smaller area within a semiconductor substrate. As the density of elements is increased, a higher flatness is required.

In chemical mechanical polishing (CMP), a polishing pad prepared from a urethane material is used together with a slurry to polish the wafers. The slurry includes polishing particles, such as aluminum oxide, cerium oxide or silica particles, dispersed in an aqueous medium. The slurry is present between the CMP polishing pad and surface of the wafers during the CMP process, so that the slurry mechanically and chemically polishes the surface of the wafers and then is discharged to the outside. In order for the slurry to be present on the CMP polishing pad for a predetermined period of time, the CMP polishing pad needs to store the slurry therein. Such a slurry storage function of the CMP polishing pad may be carried out by pores formed in the polishing pad. That is, the slurry may permeate into the pores formed in the CMP polishing pad and thus efficiently polish a surface of a semiconductor for a long time. In order for the CMP polishing pad to suppress discharge of the slurry as much as possible and make a high polishing efficiency, a shape of the pores needs to be controlled and the properties, such as hardness, of the polishing pad need to maintain optimum conditions. The polishing particles generally range in size from 100 nm to 200 nm. The slurry further includes other agents such as surface acting agents, oxidizing agents, or pH regulators. The urethane pad is weaved to have channels or perforations helpful in distributing the slurry across whole surface of the pad and the wafer and removing the slurry and slurry fragments. In one type of polishing pad, hollow, spherical microelements are distributed throughout the urethane material. As a surface of the pad is worn away through use, the microelements provide a continually renewable surface texture.

In this regard, Korean Patent Laid-open Publication No. 2015-0026903 discloses a chemical mechanical polishing pad. However, if a physical foaming agent is used to form pores in the chemical mechanical polishing pad, the physical foaming agent may remain on the pad and cause damage to a wafer.

Meanwhile, the use of copper as a connection material has been on the increase due to its low resistance. Typically, an etching technique is employed to flatten conductive (metal) and insulating surfaces. In this regard, the CMP process causes many defects during polishing of a low-k material and a copper wire. If the low-k material is used for a copper inlay technique and the CMP process is performed, the low-k material may be deformed or damaged under a high mechanical pressure, so that a local defect may be formed in a substrate surface. Further, during polishing of the copper wire, a local defect such as dishing of the copper wire and erosion of a dielectric layer caused by overpolishing of the substrate surface may be formed. Furthermore, another layer such as a barrier layer may be removed in a non-uniform manner.

SUMMARY

In view of the foregoing, the present disclosure provides a porous polishing pad including pores formed by a reaction between a prepolymer and a saccharide material, and a method of preparing the porous polishing pad.

However, problems to be solved by the present disclosure are not limited to the above-described problems. Although not described herein, other problems to be solved by the present disclosure can be clearly understood by those skilled in the art from the following descriptions.

MEANS FOR SOLVING THE PROBLEMS

In accordance with a first aspect of the present disclosure, there is provided a method of preparing a porous polishing pad, including: dispersing a saccharide material in a prepolymer; and preparing a polishing pad in which pores are formed in the prepolymer by a reaction between the prepolymer and the saccharide material.

In accordance with a second aspect of the present disclosure, there is provided a porous polishing pad prepared by the method according to the first aspect of the present disclosure and including pores which are chemically and physically formed by a saccharide material.

EFFECT OF THE INVENTION

Conventionally, when a porous polishing pad is prepared, a physical foaming agent or chemical foaming agent has been used to form pores in a pad. Particularly, if a porous polishing pad including pores which is prepared by using the physical foaming agent is used in a chemical mechanical polishing process, the physical foaming agent may remain on the porous polishing pad and thus cause damage to a wafer. Further, conventionally, a polishing solution (slurry) is discharged through a hole mechanically formed in the polishing pad, and, thus, the polishing solution may remain on a polishing target substrate for a long time and thus can cause damage to the polishing target substrate.

However, in accordance with an embodiment of the present disclosure, a porous polishing pad is prepared without using a physical foaming agent, but the porous polishing pad including pores formed by a physical chemical reaction between a prepolymer and a saccharide material can be prepared. Further, according to an embodiment of the present disclosure, if a polishing target substrate is polished using the porous polishing pad including pores in the entire polishing pad, a polishing solution can be discharged through the pores formed in the entire polishing pad. Thus, a polishing rate becomes uniform and a surface quality of the polishing target is improved. Particularly, in accordance with an embodiment of the present disclosure, the saccharide material may be dissolved by the polishing solution or diluted water during a chemical mechanical polishing process and thus may form additional pores in the porous polishing pad. Herein, the saccharide material is dissolved in the polishing solution or distilled water and thus does not remain on the polishing pad and does not damage the polishing target. Further, since the saccharide material is also used as a corrosion inhibitor for metal, if a metal thin film is chemically and mechanically polished, the saccharide material can also function to protect the metal thin film. In accordance with an embodiment of the present disclosure, an endothermic reaction occurring when the saccharide is dissolved by the polishing solution or deionized water on a surface of the polishing pad suppresses an increase in temperature of the polishing pad to a high temperature. Thus, after polishing, the uniformity of the polishing target substrate can be improved.

Further, in an embodiment of the present disclosure, as for pores formed by a reaction between a prepolymer and a saccharide material, it is possible to easily control a size and/or porosity of pores to be formed, since the reaction between the prepolymer and the saccharide material can be controlled by regulating a temperature of the reaction, a stirring speed, a stirring time, and the like. Further, porosity of pores to be formed can be easily controlled depending on the amount of added saccharide material.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a porous polishing pad in accordance with an embodiment of the present disclosure.

FIG. 2 is a schematic diagram illustrating a porous polishing pad in accordance with an embodiment of the present disclosure.

FIG. 3 is a schematic diagram illustrating a porous polishing pad in accordance with an embodiment of the present disclosure.

FIG. 4A and FIG. 4B show cross-sectional SEM images of a porous polishing pad in accordance with an example of the present disclosure.

FIG. 5A and FIG. 5B show surface SEM images of a porous polishing pad in accordance with an example of the present disclosure.

DETAILED DESCRIPTION

Hereinafter, examples of the present disclosure will be described in detail with reference to the accompanying drawings so that the present disclosure may be readily implemented by those skilled in the art. However, it is to be noted that the present disclosure is not limited to the examples but can be embodied in various other ways. In drawings, parts irrelevant to the description are omitted for the simplicity of explanation, and like reference numerals denote like parts through the whole document

Through the whole document, the term “connected to” or “coupled to” that is used to designate a connection or coupling of one element to another element includes both a case that an element is “directly connected or coupled to” another element and a case that an element is “electronically connected or coupled to” another element via still another element.

Through the whole document, the term “on” that is used to designate a position of one element with respect to another element includes both a case that the one element is adjacent to the another element and a case that any other element exists between these two elements.

Through the whole document, the term “comprises or includes” and/or “comprising or including” used in the document means that one or more other components, steps, operation and/or existence or addition of elements are not excluded in addition to the described components, steps, operation and/or elements unless context dictates otherwise. The term “about or approximately” or “substantially” are intended to have meanings close to numerical values or ranges specified with an allowable error and intended to prevent accurate or absolute numerical values disclosed for understanding of the present disclosure from being illegally or unfairly used by any unconscionable third party. Through the whole document, the term “step of” does not mean “step for”.

Through the whole document, the term “combination of” included in Markush type description means mixture or combination of one or more components, steps, operations and/or elements selected from a group consisting of components, steps, operation and/or elements described in Markush type and thereby means that the disclosure includes one or more components, steps, operations and/or elements selected from the Markush group.

Through the whole document, a phrase in the form “A and/or B” means “A or B, or A and B”.

Through the whole document, the term “saccharide material” refers to “a compound which has relatively small molecules from among carbohydrates and is dissolved in water, resulting in a sweet taste, and includes a monosaccharide material, a disaccharide material, and a polysaccharide material.

Hereinafter, embodiments and examples of the present disclosure will be described in detail with reference to the accompanying drawings. However, the present disclosure may not be limited to the embodiments and examples.

In accordance with a first aspect of the present disclosure, there is provided a method of preparing a porous polishing pad, including: dispersing a saccharide material in a prepolymer; and preparing a polishing pad in which pores are formed in the prepolymer by a reaction between the prepolymer and the saccharide material.

In this regard, FIG. 1 is a schematic diagram illustrating a porous polishing pad in accordance with an embodiment of the present disclosure.

Referring to FIG. 1, the porous polishing pad in accordance with an embodiment of the present disclosure may include a polishing pad 100 including pores.

FIG. 2 is a schematic diagram illustrating a porous polishing pad in accordance with an embodiment of the present disclosure.

In an embodiment of the present disclosure, the polishing pad 100 may further include an auxiliary pad 200 attached to a lower part of the polishing pad 100, but may not be limited thereto.

In an embodiment of the present disclosure, each of the polishing pad 100 and the auxiliary pad 200 may include urethane foam, but may not be limited thereto.

In an embodiment of the present disclosure, the prepolymer includes polyisocyanate and is used to prepare urethane foam constituting a matrix of the polishing pad. In an embodiment of the present disclosure, the polyisocyanate may be used without particular limitation as long as it is an organic compound including two or more isocyanate groups in a molecule. For example, the polyisocyanate may include aliphatic, alicyclic, and aromatic polyisocyanates or modified compounds thereof. To be specific, the aliphatic and alicyclic polyisocyanates may include hexamethylene diisocyanate or isophoronediisocyanate, but may not be limited thereto. The aromatic polyisocyanates may include tolylene diisocyanate, diphenyl methane diisocyanate, polyphenylene polymethylene polyisocyanate, or modified compounds thereof such as carbodiimide-modified compounds or prepolymers thereof, but may not be limited thereto.

In an embodiment, the urethane foam may be prepared through a reaction between isocyanate and an isocyanate-terminated urethane prepolymer from prepolymer polyol. For example, the polyol may include a member selected from the group consisting of polypropylene ether glycol, polytetramethylene ether glycol, polyether glycol, polypropylene glycol, polycarbonate diol, and combinations thereof, or copolymers thereof, but may not be limited thereto. To be specific, the reaction between the isocyanate and the isocyanate-terminated urethane prepolymer may be carried out by reacting a urethane prepolymer such as isocyanate, di-isocyanate, and tri-isocyanate prepolymers with a prepolymer, such as polyol, containing isocyanate reactive residues. Desirably, the isocyanate reactive residues may include amine and polyol, but may not be limited thereto.

In an embodiment of the present disclosure, the polishing pad may be prepared using the above-described polymer resins, and a synthesizing method widely known in the art may be used without a specific limitation. For example, if a main body of the polishing pad is prepared from a polyurethane-based compound, a prepolymer method or a one-shot method may be used to prepare the polishing pad. For example, if the polishing pad is prepared using the prepolymer method, a urethane prepolymer is formed by reacting a polyol component and an isocyanate component and then, the urethane prepolymer, diamine or diol, a foaming agent, and a catalyst are mixed and cured, so that a polyurethane-based resin can be formed. For example, if the polishing pad is formed using the one-shot method, a polyol component, an isocyanate component, diamine or diol, a foaming agent, and a catalyst are mixed and cured, so that a polyurethane-based resin can be formed.

Further, in an embodiment of the present disclosure, in addition to the polymer resin and the saccharide material, an additive and/or adjuvant may be used as being mixed with the polymer resin, e.g., polyisocyanate component, depending on a use, but the present disclosure may not be limited thereto. The additive and/or adjuvant is not particularly limited as long as it is used to improve the properties or processibility of a typical resin but does not have a noticeable bad influence on an urethanization.

In this regard, FIG. 3 shows an enlarged schematic diagram of a porous polishing pad in accordance with an embodiment of the present disclosure. As illustrated in FIG. 3, in an embodiment of the present disclosure, an unreacted saccharide material 130 which does not react with the prepolymer may be dispersed on the pores, but may not be limited thereto.

As illustrated in FIG. 1 through FIG. 3, the porous polishing pad in accordance with embodiment of the present disclosure includes the pores formed in the entire polishing pad. Therefore, if a polishing target substrate is polished using the porous polishing pad in accordance with embodiment of the present disclosure, a polishing solution can be efficiently supplied to the polishing target substrate through the pores formed in the entire polishing pad.

In an embodiment of the present disclosure, the saccharide material may include a monosaccharide material, a disaccharide material, and a polysaccharide material, but may not be limited thereto. For example, desirably, the saccharide material may include a sugar-alcohol, but may not be limited thereto.

In an embodiment of the present disclosure, the saccharide material may be chemically bonded to the prepolymer or physically distributed in the prepolymer, but may not be limited thereto. In an embodiment of the present disclosure, the pores may be chemically formed through pyrolysis, alcohol dehydration, alcohol cyclization, hydrogenation, or hydrogenolysis of the saccharide material. In an embodiment of the present disclosure, the pores may be physically formed by dispersing a solid or liquid saccharide material within urethane.

In an embodiment of the present disclosure, the saccharide material may be contained in the amount of from about 1 part by weight to about 70 parts by weight with respect to 100 parts by weight of the prepolymer, but may not be limited thereto. For example, the saccharide material may be contained in the amount of from about 1 part by weight to about 70 parts by weight, from about 1 part by weight to about 60 parts by weight, from about 1 part by weight to about 50 parts by weight, from about 1 part by weight to about 40 parts by weight, from about 1 part by weight to about 30 parts by weight, from about 1 part by weight to about 20 parts by weight, from about 1 part by weight to about 10 parts by weight, from about 10 parts by weight to about 70 parts by weight, from about 20 parts by weight to about 70 parts by weight, from about 30 parts by weight to about 70 parts by weight, from about 40 parts by weight to about 70 parts by weight, from about 50 parts by weight to about 70 parts by weight, or from about 60 parts by weight to about 70 parts by weight with respect to about 100 parts by weight of the prepolymer, but may not be limited thereto.

In an embodiment of the present disclosure, the saccharide material may include a member selected from the group consisting of galactose, fructose, glucose, lactose, maltose, dextrin, sucrose, glycerin, xylitol, sorbitol, arabitol, erythritol, xylitol, ribitol, mannitol, galactitol, maltitol, lactitol, and combinations thereof, but may not be limited thereto.

In an embodiment of the present disclosure, the saccharide material may include a liquid phase, a solid phase, or a mixed phase thereof, but may not be limited thereto.

In an embodiment of the present disclosure, the saccharide material in the solid phase may have a particle size of from about 0.01 μm to about 1,000 μm, but may not be limited thereto. For example, the saccharide material in the solid phase may have a particle size of from about 0.01 μm to about 1,000 μm, from about 1 μm to about 1,000 μm, from about 10 μm to about 1,000 μm, from about 100 μm to about 1,000 μm, from about 200 μm to about 1,000 μm, from about 300 μm to about 1,000 μm, from about 400 μm to about 1,000 μm, from about 500 μm to about 1,000 μm, from about 600 μm to about 1,000 μm, from about 700 μm to about 1,000 μm, from about 800 μm to about 1,000 μm, from about 900 μm to about 1,000 μm, from about 0.01 μm to about 900 μm, from about 0.01 μm to about 800 μm, from about 0.01 μm to about 700 μm, from about 0.01 μm to about 600 μm, from about 0.01 μm to about 500 μm, from about 0.01 μm to about 400 μm, from about 0.01 μm to about 300 μm, from about 0.01 μm to about 200 μm, from about 0.01 μm to about 100 μm, or from about 0.01 μm to about 10 μm, but may not be limited thereto.

In an embodiment of the present disclosure, if the saccharide material is added to the prepolymer with stirring, dispersibility can be improved. Therefore, pores can be formed uniformly in the polishing pad. In an embodiment of the present disclosure, if the polishing pad is a porous polishing pad including pores, the polishing solution is stored in the pores of the porous polishing pad during a mechanical chemical polishing process, and, thus, it is possible to efficiently polish the polishing target substrate for a long time.

In an embodiment of the present disclosure, the method of preparing a porous polishing pad may include: adding a curing agent during the reaction between the prepolymer and the saccharide material, but may not be limited thereto.

In an embodiment of the present disclosure, the curing agent may be contained in the amount of from about 20 parts by weight to about 50 parts by weight with respect to about 100 parts by weight of the prepolymer, but may not be limited thereto. For example, the curing agent may be contained in the amount of from about 20 parts by weight to about 50 parts by weight, from about 20 parts by weight to about 40 parts by weight, from about 20 parts by weight to about 30 parts by weight, from about 30 parts by weight to about 50 parts by weight, or from about 40 parts by weight to about 50 parts by weight with respect to about 100 parts by weight of the prepolymer, but may not be limited thereto.

In an embodiment of the present disclosure, the curing agent may include compounds used to cure or harden a urethane prepolymer, or mixtures of the compounds, but may not be limited thereto. The curing agent may react with an isocyanate group to connect chains of the prepolymer and thus form polyurethane. For example, the curing agent may include a member selected from the group consisting of 4,4′-methylene-bis(2-chloroaniline) (MBCA), which is often called “MOCA” (registered trademark), 4,4′-methylene-bis(3-chloro-2,6-diethylaniline) (MCDEA), dimethyl thio toluenediamine, trimethylene glycol di-p-aminobenzoate, polytetramethylene oxide di-p-aminobenzoate, polytetramethylene oxide mono-p-aminobenzoate, polypropylene oxide di-p-aminobenzoate, polypropylene oxide mono-p-aminobenzoate, 1,2-bis(2-aminophenylthio)ethane, 4,4′-methylene-bis-aniline, diethyltoluenediamine, 5-tert-butyl-2,4-toluenediamine, 3-tert-butyl-2,6-toluenediamine, 5-tert-amyl-2,4-toluenediamine, 3-tert-amyl-2,6-toluenediamine, chlorotoluenediamine, and combinations thereof, but may not be limited thereto.

In an embodiment of the present disclosure, the auxiliary pad 200 may be attached to the polishing pad 100 with an adhesive 210 and thus function as a cushion for protecting the polishing pad 100 and improve polishing uniformity.

In an embodiment of the present disclosure, the adhesive 210 may be used without particular limitation as long as it attaches the auxiliary pad 200 to the polishing pad 100 without deteriorating performance of the polishing pad 100, but may not be limited thereto.

In an embodiment of the present disclosure, in order to perform chemical mechanical polishing using the porous polishing pad, for example, a polishing target substrate may be prepared and the polishing target substrate may be chemically and mechanically polished using the porous polishing pad according to an embodiment of the present disclosure and a polishing solution. Herein, the method of preparing a porous polishing pad may further include attaching the porous polishing pad to a polishing machine with an adhesive 220.

In an embodiment of the present disclosure, a saccharide material included in the porous polishing pad in accordance with an embodiment of the present disclosure may be dissolved by the polishing solution during a chemical mechanical polishing process and thus may form additional pores in the polishing pad, but may not be limited thereto.

In accordance with a second aspect of the present disclosure, there is provided a porous polishing pad which is prepared by the method according to the first aspect of the present disclosure and including pores which are chemically and physically formed by a saccharide material.

Detailed descriptions of the porous polishing pad in accordance with the second aspect of the present disclosure, which overlap with those of the first aspect of the present disclosure, are omitted hereinafter, but the descriptions of the first aspect of the present disclosure may be identically applied to the second aspect of the present disclosure, even though they are omitted hereinafter.

Conventionally, when pores are formed in a polishing pad, it is difficult to precisely regulate a size and porosity of the pores, and it is not easy to form uniform pores of about 50 μm or less. However, in an embodiment of the present disclosure, if pores are formed in a polishing pad through a reaction between a prepolymer and a saccharide material, the reaction between the prepolymer and the saccharide material can be controlled by regulating a temperature of the reaction, a stirring speed, or a stirring time. Therefore, it is possible to easily control a pore size and porosity of the porous polishing pad.

Further, in a conventional porous polishing pad, a physical foaming agent used for forming pores in the polishing pad remains in the polishing pad even after the polishing pad is formed. In this case, the physical foaming agent causes a defect in a polishing target during a polishing process. However, in an embodiment of the present disclosure, a physical foaming agent is not used, and, thus, impurities are not generated from a foaming agent and generation of defects can be suppressed. Further, in an embodiment of the present disclosure, the saccharide material used for forming pores in the polishing pad may be dissolved in a polishing solution or distilled water and thus may form additional pores in the porous polishing pad during a chemical mechanical polishing process.

Hereinafter, examples of the present disclosure will be described in detail. However, the present disclosure may not be limited thereto.

EXAMPLES 1. A Method of Preparing Porous Polishing Pad

50 parts by weight of mannitol (or 40 parts by weight of sorbitol) was added as a saccharide material to 100 parts by weight of a urethane prepolymer (TDI/MDI/PTMGE-based NCO eq=8.1^(˜)10.3%) and then mixed. Herein, 20 parts by weight to 50 parts by weight of MOCA was added as a curing agent thereto and stirred. Herein, the curing agent was added after calculating a stoichiometric equivalent ratio according to the NCO content and equivalent ratio of the prepolymer. Then, the mixture was coated on a heated substrate and then molded under pressure. The molded pad was cured at 96.5° C. for 16 hours and then processed to a thickness of 100 mils. Then, a groove was formed in a polishing surface, so that a porous polishing pad was prepared.

2. Polishing Method Using Porous Polishing Pad

The polishing pad prepared in Example 1 was attached to a wafer polishing machine (AP-300) on the market and then, the polishing target wafer was polished. The polishing pad was conditioned for from about 15 minutes to about 20 minutes before the wafer was polished. The wafer was polished using a silica-based polishing solution on the market. The polishing conditions were equally applied to the present example and all of the other examples to directly compare the performance: a pressure of 9 psi; a press plate speed of 95 rpm; a carrier speed of 90 rpm; and a polishing time of 1 minute.

TEST EXAMPLES

After the polishing pad prepared in Example 1 and the wafer polishing machine were used to polish the polishing target wafer, a thin film thickness was measured using a ST-3000 manufactured by K-MAC. After the polishing pad prepared in Example 1 and the wafer polishing machine were used to polish the polishing target wafer, a thin film thickness was 4,672 Å/min. In case of using an expancel which has been conventionally used as a physical foaming agent, a thin film thickness after polishing was 4,480 Å/min. As described above, it could be seen that the porous polishing pad prepared by using the saccharide material according to the present example had the polishing efficiency similar to that of the porous polishing pad prepared by using the conventional physical foaming agent.

FIGS. 4A and 4B and FIGS. 5A and 5B are SEM images of the porous polishing pad prepared according to Example 1. FIG. 4A and FIG. 4B are cross-sectional SEM images of the porous polishing pad including 40 parts by weight of a saccharide material, and FIG. 5A and FIG. 5B are surface SEM images of the porous polishing pad including 40 parts by weight of a saccharide material. The porous polishing pad using the saccharide material as described in Example 1 included pores which are chemically and physically formed by the saccharide material. All the physically dispersed saccharide material was dissolved and removed by deionized water before and after the polishing target wafer was polished. Further, even when the saccharide material was exposed on the surface by a conditioner during polishing, it was dissolved by the polishing solution. The saccharide material is also used as a corrosion inhibitor for metal and does not include a physical expancel unlike a porous polishing pad including the conventional physical foaming agent. Thus, the saccharide material is considered as favorable in terms of damage.

The above description of the present disclosure is provided for the purpose of illustration, and it would be understood by those skilled in the art that various changes and modifications may be made without changing technical conception and essential features of the present disclosure. Thus, it is clear that the above-described examples are illustrative in all aspects and do not limit the present disclosure. For example, each component described to be of a single type can be implemented in a distributed manner. Likewise, components described to be distributed can be implemented in a combined manner.

The scope of the present disclosure is defined by the following claims rather than by the detailed description of the embodiments. It shall be understood that all modifications and embodiments conceived from the meaning and scope of the claims and their equivalents are included in the scope of the present disclosure.

EXPLANATION OF CODES

-   -   100: Polishing pad     -   110: Pores formed by reaction of saccharide material     -   120: Physically dispersed saccharide material     -   130: Saccharide material     -   200: Auxiliary pad     -   210, 220: Adhesive 

1. A method of preparing a porous polishing pad, comprising: dispersing a saccharide material in a prepolymer; and preparing a polishing pad in which pores are formed in the prepolymer by a reaction between the prepolymer and the saccharide material.
 2. The method of preparing a porous polishing pad of claim 1, wherein an unreacted saccharide material which does not react with the prepolymer is dispersed on the pores.
 3. The method of preparing a porous polishing pad of claim 1, wherein the saccharide material includes a monosaccharide material, a disaccharide material, or a polysaccharide material.
 4. The method of preparing a porous polishing pad of claim 3, wherein the polysaccharide material includes a sugar-alcohol.
 5. The method of preparing a porous polishing pad of claim 1, wherein the saccharide material includes a member selected from the group consisting of galactose, fructose, glucose, lactose, maltose, dextrin, sucrose, glycerin, xylitol, sorbitol, arabitol, erythritol, ribitol, mannitol, galactitol, maltitol, lactitol, and combinations thereof.
 6. The method of preparing a porous polishing pad of claim 1, wherein the saccharide material includes a liquid phase, a solid phase, or a mixed phase thereof.
 7. The method of preparing a porous polishing pad of claim 6, wherein the saccharide material in the solid phase has a particle size of from 0.01 μm to 1,000 μm.
 8. The method of preparing a porous polishing pad of claim 1, wherein a curing agent is added during the reaction between the prepolymer and the saccharide material.
 9. The method of preparing a porous polishing pad of claim 8, wherein the curing agent includes a member selected from the group consisting of 4,4′-methylene-bis(2-chloroaniline), 4,4′-methylene-bis(3-chloro-2,6-diethyl aniline), dimethyl thio toluenediamine, trimethylene glycol di-p-aminobenzoate, polytetramethylene oxide di-p-aminobenzoate, polytetramethylene oxide mono-p-aminobenzoate, polypropylene oxide di-p-aminobenzoate, polypropyleneoxide mono-p-aminobenzoate, 1,2-bis(2-aminophenylthio)ethane, 4,4′-methylene-bis-aniline, diethyltoluenediamine, 5-tert-butyl-2,4-toluenediamine, 3-tert-butyl-2,6-toluenediamine, 5-tert-amyl-2,4-toluenediamine, 3-tert-amyl-2,6-toluenediamine, chlorotoluenediamine, and combinations thereof.
 10. A porous polishing pad including pores which are chemically and physically formed by a saccharide material, which is prepared by the method of claim
 1. 